Electric converter for luminous tubes



Oct. 30,1934. goERsTE 1,978,528

ELECTRIC CONVERTER FOR LUMINOUS TUBES Filed Jan. 25, 1950 Max/1114 1 5192.523

INVENTOR Patented Oct. 30, 1934 V n ELECTRIC CONVERTER FOR LUMINOUS TUBES William Foerste, Pelham Manor, N. Y., assignor to Adolph Josepowitz, New York, N. Y., and to said William Foerste 7 Application January 23, 1930, Serial No. 422,898 2 Claims; (01. 2505-36) 1 The present application is a continuation in are connected directly to the pair of wires 4 compart of my application Serial No. 394,125, filed prisingthe power leads. Sept. 20, 1929. The variable resistance 9 is provided to per-,

' This invention relates to converting systems mit adjustment of the filament current while "I and apparatus for the conversion of arelatively the resistances 7 are provided to. by-pass the low voltage direct current into a high voltage plate current of the tubes 1 and 2. No by-pass oscillatory current for use inoperating luminous resistance is required for the tube 2 since the tubes or for any other purpose in which a high plate current of none of the tubes can pass voltage current isto be used. through the tube 2. The resistances 8 are pro- 10 The broad object of the present invention is vided to reduce the supply voltage to a safe value to provide a system of connections and appafor heating the filaments of the vacuum tubes. ratus including power oscillator tubes adapted There is provided a transformer comprising a to receive a direct current at a voltage, let us core 11 of magnetic material upon which is say 125 volts or even more, and convert it into provided'a plurality of coils 12a, 12b, 12c and II a high voltage current capable of operating 12d respectively, for a purpose now to be deapparatus or devices such as luminous signs'for scribed. The grids of all of the oscillator tubes in tan e. v i 1 and 2 are connected in parallel and the com- A further object is to provide an improved mon Wire is connected to one end of the coil converter for direct'currents which dispenses 12a, the other end of the coil 12a being con- 20 with the use of a motor generator'for producing nected to the negative side of the direct current the high voltage, high frequency current necesupply ho- One end of the coil 12b is consary for operation of luminous signs andother nected to the wire lea to the common condevices in which high frequency current is used. otio Of h grids while the other end of the Other objects and advantages of the invention coil 12b is connected to one of the terminals of 25 will be hereinafter specifically pointed out, or the luminous tube. The other terminal of the will become apparent asthe specification pro-' luminous tube is connected o n nd f the Goods. 7 coil 120; the other end of the coil 12c being with the above indicated objects in i th connected to a wire which is in turn connected invention resides in certain novel constructions; to all Of plates o t e tubes. One end of v 30 combinations and e gnt t the'coil 12d islikewisebonnected to the comclearly described in the followingspecificatioh H1011 Wife to t P a d t e other end is and fully illustrated in-the accompa y CPnHeQted Wi positive id t T' ing, which latter shows embodiments of the inn line- Preferably the coil 12a may consist vention as at present preferred. of eight hundred turns while the coils 12b and 5 In said drawing: 120 have five thousand turns each. The coil 12d 96 The ingle sheet of drawings represents 3, diais preferably 0f one thousand turns. COllS 12a grammatic arrangement of apparatus for aca 121), being cohnectod in 891168, y be concomplishing the desired objects, the numerals l Sui-fired as One P011, W e 6 15 0 d and 2 representing a number of power oscillator ing COIlnected Series, may also be considered .Oj'tubes which in the present case are adapted to as one 0011. All Of the coils are wound So that ,act as oscillation generators for the production if they were c cted in Series the ic of an alternating current for operating a lumiforces p u d Would be added 110 each other, nous ign 3, h i it including th pair of in other words the coils are additively wound. wires 4 may be connected by means of a suitable the D D 0f proteoting t e transformer 45.. attachment plug 5 to a source of direct current m possible high V e Sur s there is p 100 of say 125 volts. vided a spark gap 13 which is so adjusted that The filaments 6 of the tubes 1 are connected when the Voltage exceeds a S Value & pa k in shunt relation to by-pass resistances 7 which discharge W111 000111" relieving t e transformer are connected in series with fixed resistances 8,. windings 0f the Strain p d by excessive volt- Kil a variable resistance 9 and the filament 6 of the age- Prefe y the park gap is mounted as oscillator tube 2. A condenser 10 of suitable near as possible to the transformer as will be capacity. is connected in shunt with one of the readily understood by persons skilled in the art. fixed resistances 8 and the variable resistance 9. A condenser 14 of suitable capacity to by-pass The entire series circuit comprising the resisthigh voltage alternating currents produced by Igl5 ances 7, 8 and 9 and the filament 6 of tube 2 the oscillators is connected across the lead wires ll-(l 4. The condenser 14 prevents the alternating currents produced by the tubes from causing interference with the operation of radio apparatus in the vicinity of the converter. It is contemplated that the entire converter be shielded by enclosing it in a suitable compartment of metal so as to prevent radiation of energy which might cause interference with telephone lines and radio apparatus. It has been found in practice that a condenser of about 1 m. f. capacity connected between the shield 16 and one of the power leads i is desirable and beneficial in preventing radiation of energy which might interfere with nearby radio the point where the coil is connected to the common junction of the filament circuit and the 20 positive of the lead wires 4. If desired an incandescent lamp of suitable size may be substituted for either of the resistances 8 and the power which would otherwise be dissipated in the form of heat may be utilized for illuminative 25, purposes and also serve as a pilot light to indicate that the filaments are energized.

The circuit including the condenser 10, oscillators l and 2 and the transformer comprises an oscillatory circuit capable of producing a high voltage alternating current of high frequency which may be used to operate suitable apparatus or devices wherein such a current is needed. The invention has been described as being used in connection with a luminous tube 352 comprising an advertising sign but it is to be understood that it may be used for other purposes as well.

It may be found necessary to alter the ratio of coils 12a, 12b, 12c and 12d or in some cases 0 tov place an independent winding or coil upon 'the oscillating transformer in order to successfully operate the auxiliary device, it depending upon what the device constitutes.

One of the important advantages of the pres- 45, .ent invention is the elimination of the motor generator which is usually required to convert direct current to high frequency alternating current.

The hereinbefore described construction ad- .mits of considerable modification without departing from the invention; therefore, it is the wish, not to be limited to the precise arrangements shown and described, which are as aforesaid, by way of illustration merely. In other words, the scope of protection contemplated is to be taken solely from the appended claims, interpreted as broadly as is consistent with the prior art.

What is claimed as new, is:

1. Apparatus for converting a relatively low voltage commercial power line current into a high voltage alternating current, for operating luminous tubes and analogous high voltage devices, comprising in combination a first coil, one terminal of which is connected to one side of the line and the other terminal of which is connected to one side of the high voltage device constituting the load, a second coil, one terminal of which is connected to the other side of the line and the other terminal of which is connected to the other side of the high voltage device constituting the load, said coils being inductively coupled, and oscillation generating means, comprising at least one thermionic tube, the plate of which is connected into the body of one of said coils, at a point intermediate the described terminals thereof, and the grid of which is connected into the body of the other of said coils, at a point intermediate the described terminals thereof and the cathode of which is connected across the line.

2. Apparatus for converting a relatively low voltage commercial power line current into a high voltage alternating current, for operating luminous tubes and analogous high voltage devices, comprising in combination a first coil, one terminal of which is connected to one side of the line and the other terminal of which is con- 110 nected to one side of the high voltage device constituting the load, a second coil, one terminal of which is connected to the other side of the line and the other terminal of which is connected to the other side of the high voltage device constituting the load, said coils being inductively coupled, and oscillation generating means, comprising a plurality of thermionic tubes, the plates of which are in parallel and are connected into the body of one of said coils, at a point intermediate the described terminals thereof, the grids of which are in parallel and are connected into the body of the other of said coils, at a point intermediate the described terminals thereof, and the cathodes of which are connected 12.5 across the line.

WILLIAM FOERSTE. 

